The present invention relates to bulb-form lamps.
In a conventional lamp such as a bulb-form fluorescent lamp, as shown in FIG. 6, a fluorescent tube 4, a lighting circuit 5 to light this fluorescent tube 4, and two lead wires 11a and 11b brought into connection with this lighting circuit 5 and supplying power thereto are housed in an envelope 19 comprising a globe 1 and a case 18.
At one end of the case 18, a base 20 is screwed in. This base 20 has a screw-form shell 20a and an eyelet 20c provided at one end of this shell 20a via glass-made insulator 20b. Portions respectively of the shell 20a and the eyelet 20c are embedded into the insulator 20b, and thereby the shell 20a, the insulator 20b, and the eyelet 20c are integrated.
One lead wire 11a is brought into connection with the base 20 on the outside, that is, onto the outer surface of the eyelet 20c by soldering.
Also, the lead wire 11a and the eyelet 20c are brought into connection by plasma arc welding from the environmental view point.
The manufacturing method of such a conventional lamp is as follows.
After an envelope 19, a fluorescent tube 4, and a lighting circuit 5 with which lead wires 11a and 11b are brought into connection are assembled by means of a normal method, the base 20 is screwed into one end portion of the case 18 and undergoes caulking to be fixed into the case 18. In that occasion, one lead wire 11a is arranged to be led out from a through hole 20d formed in the eyelet 20c. In addition, the portion led out from this lead wire 11a is brought into connection with the outer surface of the eyelet 20c by means of soldering or plasma arc welding.
However, in such a conventional lamp, in the case where the lead wire 11a is brought into connection with the eyelet 20c, flux (resin, etc.) used for soldering is formed as a film on the surface of soldering, and therefore, such a base 20 installed in a socket (not shown) of an illumination equipment causes the contact between the eyelet 20c and the socket to be incomplete. In addition, the eyelet 20c is corroded by this flux so that the eyelet 20c suffers from incomplete contact with the socket. There was a problem that due to such incomplete contact, lamps fail to be lighted.
In addition, there was a problem that the case where the lead wire 11a is brought into connection with the eyelet 20c by means of plasma arc welding gives rise to total costs since the plasma arc welding apparatus is expensive, requires a large installation space, and needs a lot of maintenance work.
The present invention has been achieved to solve these problems, and provides a low cost bulb-form lamp and a manufacturing method therefor, in which a lead wire is brought into connection with an eyelet easily and reliably without applying soldering or plasma arc welding, thereby preventing lighting failure due to incomplete contact is prevented.
A bulb-form lamp of the present invention includes a base having a screw form shell and an eyelet provided at an end portion of this shell via an insulator, and is configured so that a lead wire supplying power is brought into connection with a portion of the eyelet at other than the outer surface of the eyelet.
In addition, a first manufacturing method of a bulb-form lamp of the present invention is a method for manufacturing a bulb-form lamp including a base having a screw form shell and an eyelet provided in an end portion of this shell via an insulator, wherein a lead wire supplying power is brought into connection with a portion of the eyelet at other than the outer surface of the above described eyelet, comprising the steps of: leading out the lead wire from an eyelet receiving section formed in the insulator; bringing an end portion of the led out lead wire into connection with the eyelet; and fitting the eyelet into the eyelet receiving section.
The above described lamp and the manufacturing method therefor can bring the lead wire into connection with the eyelet easily and reliably without applying soldering or plasma arc welding and therefore, the failure of lighting due to incomplete contact can be prevented and cost saving can be achieved.
A second manufacturing method of the present invention is a method for manufacturing a bulb-form lamp including a base having a screw form shell and an eyelet provided at an end portion of this shell via an insulator, wherein a lead wire supplying power is brought into connection with a portion of the eyelet at other than the outer surface of the eyelet, comprising the steps of: leading out the lead wire from an eyelet receiving section formed in the insulator; disposing the led out lead wire along a side surface of the eyelet receiving section; fitting the eyelet into the eyelet receiving section; and sandwiching the lead wire between the eyelet and the insulator.
According to the above described manufacturing method, the lead wire can be brought into connection with the eyelet easily and reliably without applying soldering or plasma arc welding and therefore, the failure of lighting due to incomplete contact can be prevented and cost saving can be achieved. Also, without applying caulking or resistance welding, the lead wire can be brought into connection with the eyelet, and thus the manufacturing process can be simplified and production efficiency can be improved.